1. Field of the Invention
The present invention relates to recording media for an inkjet printer, and more particularly, to recording media for an inkjet printer having multi-layered coatings of two or more ink receiving layers comprising at least a pigment and a binder on a substrate.
2. Description of the Related Art
Inkjet printing has gained wide acceptance by consumers in the printing industry because it is fast in printing speed and is a relatively inexpensive form of printing and yet it produces high resolution printed images.
In inkjet printers, various kinds of recording media including ordinary paper, specially coated paper or printing dedicated films, are used, and photopaper for use in an inkjet printer is one of the recording media.
The photopaper for inkjet printers is prepared by coating materials having good ink absorption and fixation properties and good water and light resistance on a substrate, such as one side coated or double side coated art paper, cast-coated paper, resin-coated paper, synthetic paper or a plastic film, and is used in digital photography or image printing using thermal, piezo or phase change inkjet printers. The photopaper for the inkjet printers is also applied to decorating or designing of outer walls, advertising and so on.
Along with development of the inkjet printers based on inkjet recording methods, a variety of inkjet recording media are being developed for commercialization.
For example, U.S. Pat. No. 5,958,564 describes an inkjet recording sheet having two ink receiving layers on a paper support member exhibiting a good ink absorption property. However, since particle sizes of silica used in a second ink receiving layer are larger than those of silica used in a first ink receiving layer, that is, at least 7 μm, it is quite difficult to obtain a highly glossy surface just by using the two ink receiving layers.
U.S. Pat. No. 5,576,088 discloses an inkjet recording sheet having an ink receiving layer coated on a support and a gloss-providing layer formed on the ink receiving layer. In this disclosure, the support is prevalently paper. Thus, it is difficult to apply the disclosed inkjet recording sheet to films.
Inkjet paper is largely classified into resin paper having a binder as a main component, and porous paper having a microporous pigment as a main component. Inkjet photopaper is typically the porous paper exhibiting a quick ink drying property and good water resistance. In order to obtain excellent ink absorption, it is necessary for an ink receiving layer to have a thickness of at least 30 μm. In some cases, coating of ink receiving layers for the porous paper, which are much thicker than those for the resin paper, may be employed, which is quite unfavorable in view of processability and coating surface properties. A multi-layered ink receiving layer, including an ink absorbing layer, an ink fixation layer, an ink permeation layer and/or an ink protecting (gloss-providing) layer, generally has better properties than a single-layered ink receiving layer. However, the multi-layered ink receiving layer is difficult to attain. In some other cases, a coating layer having a microporous pigment as one of main components may be coated on another coating layer having another microporous pigment as one of main components. In such cases, if a film based support member with a poor absorbing property is used, pinholes, cratering, orange-peeling or foams may be generated, thereby deteriorating coating surface properties.